Added Build & Install (using cargo) (#271)

* added Install using cargo, build for all OS

* added small info on optimized binary

* minor info modification

* minor change

* updated as per comment

https://github.com/subspace/pulsar/pull/271\#discussion_r1347247886

README.md

@@ -18,11 +18,11 @@ Instead of running a terminal instance for the farmer, and running another termi
 
 ## How to Use (commands)
 
-1. download the executable from [releases](https://github.com/subspace/pulsar/releases)
-2. in your terminal, change your directory to where you download the file for example: if you downloaded your file to your `Downloads` folder, `cd Downloads`)
-3. we will address your executable name as `pulsar`, change the below commands accordingly to your full executable name.
-3. run `./pulsar init` -> this will initialize your config file, which will store the necessary information for you to farm.
-4. run `./pulsar farm` -> this will start farming. Yes, it is that simple! Enjoy!
+1. Download the executable from [releases](https://github.com/subspace/pulsar/releases)
+2. In your terminal, change your directory to where you download the file for example: if you downloaded your file to your `Downloads` folder, `cd Downloads`.
+3. We will address your executable name as `pulsar`, change the below commands accordingly to your full executable name.
+4. Run `./pulsar init` -> this will initialize your config file, which will store the necessary information for you to farm.
+5. Run `./pulsar farm` -> this will start farming. Yes, it is that simple! Enjoy! 🎉
 
 ## Other commands
 
@@ -51,7 +51,7 @@ $ ./pulsar farm
 
 Once it's running, you can detach the process by pressing `CTRL+b d` (read more about [detaching a sessions](https://linuxhint.com/detach-session-tmux/))
 
-That's it, you should be back to your terminal, with *subspace farming* running in the background as a session.
+That's it, you should be back to your terminal, with _subspace farming_ running in the background as a session.
 
 To re-attach to your session, use tmux:
 
@@ -67,7 +67,6 @@ tmux kill-session -t farming
 
 ### Example with `screen`
 
-
 ```sh
 screen -S farming
 ```
@@ -91,3 +90,79 @@ If you ever want to delete/kill your farming session, enter the command:
 ```sh
 screen -S farming -X quit
 ```
+
+## Developer
+
+### Pre-requisites
+
+You'll have to have [Rust toolchain](https://rustup.rs/) installed as well as LLVM, Clang and CMake in addition to usual developer tooling.
+
+Below are some examples of how to install these dependencies on different operating systems.
+
+#### Ubuntu
+
+```bash
+sudo apt-get install llvm clang cmake
+```
+
+#### macOS
+
+1. Install via Homebrew:
+
+```bash
+brew install llvm@15 clang cmake
+```
+
+2. Add `llvm` to your `~/.zshrc` or `~/.bashrc`:
+
+```bash
+export PATH="/opt/homebrew/opt/llvm@15/bin:$PATH"
+```
+
+3. Activate the changes:
+
+```bash
+source ~/.zshrc
+# or
+source ~/.bashrc
+```
+
+4. Verify that `llvm` is installed:
+
+```bash
+llvm-config --version
+```
+
+### Build from Source
+
+Ensure the [pre-requisites](#pre-requisites).
+
+And then run:
+
+```sh
+$ cargo build
+```
+
+> Use `--release` flag for a release build and optimized binary - `./target/release/pulsar`
+
+### Install CLI
+
+#### Using cargo
+
+After ensuring the [pre-requisites](#pre-requisites), just run:
+
+```sh
+$ cargo run --release
+```
+
+This would generate an optimized binary.
+
+And then, you can install the binary (optimized) to your system:
+
+```sh
+$ cargo install --path .
+```
+
+The binary gets added to `~/.cargo/bin`, which is included in the PATH environment variable by default during installation of Rust tools. So you can run it immediately from the shell.
+
+Using this, one doesn't need to download the executable (binary) from the [releases](https://github.com/subspace/pulsar/releases) page each time when there is a new release. They just need to pull the latest code (if already maintained) from the repository and build it locally.